"Straight away everything started going foggy and I kind of lost myself for a second."

After that, she described her partner "grabbing her shoulder", kneeing her in the chest and putting his hand over her neck.

"I couldn't breathe in and I couldn't breathe out and there was just these few seconds left and I knew I wouldn't last," she added.

"I just remember those last moments looking at Alex."

When Ms Breha did manage to call an ambulance she said Iheanacho had to be put on the phone because she was too emotional.

"I heard two things he said, the first of which is that he fell from the climbing [frame] in the play area," she said.

But by the time they got to Lewisham Hospital, she said Iheanacho "mentioned that Alex fell off of his shoulder" and later suggested "that he hit himself in the play area".

"I remember him saying that all the bruises on his face happened from him trying to wake Alex up," she said.

When asked if Alex left the house with any bruises or marks on him, she told the court: "My son never had no bruises whatsoever."

In further evidence this afternoon, the court heard that Iheanacho admitted hitting him previously in a chilling diary entry three months before the boy's alleged murder.

The diary entry by Iheanacho entitled 'mistakes' was read to the jury at Woolwich Crown Court.

In the entry from August he admitted to beating Alex after the boy had been sick in a taxi.

Iheanacho wrote: "If I think about all my mistakes, shame take over and I find myself overwhelmed in anger.

"My anger help me to push forward but fears helps me to fly high. Up up and away.

"Do I really love Alex, five years old small cute lil boy. Who want nothing more, than daddy mills to love him protect him but most of all keep him from harm - even though I had to beat him just now for sicking up in the cab - why why why I say - so the answer is yes yes yes I love him and like with all my heart but may not enough- I am real, faithful making money - so why ain't I happy."